nested level section closing

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

I am facing problem while doing the nested level closing section tags. Can somebody help out for me? i am new for this group. Input:

<h1>Heading level 1
<h2>Heading level 2
<h3>Heading level 3
<h2>Heading level 2
<h1>Heading level 1
paragraph here
paragraph here
[download]

Output:

<section1>
<head>Heading level 1</head>
<section2>
<head>Heading level 2</head>
<section3>
<head>Heading level 3</head>
</section3></section2>
<section2>
<head>Heading level 2</head>
</section2>
</section1>
<section1>
<head>Heading level 1</head>
paragraph here
paragraph here
</section1>
[download]

Your help will be very useful for me.

Comment on nested level section closing Select or Download Code

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Re: nested level section closing by GrandFather (Saint) on Mar 14, 2007 at 11:14 UTC
Use a tool designed for the job. It looks like you may be generating XML, perhaps by parsing some lightly marked up, sorta HTML, source. So lets go with that for a moment and see what can be done: use strict; use warnings; use XML::Twig; my $twig = new XML::Twig (pretty_print => 'record'); my $root = new XML::Twig::Elt ('root'); $twig->set_root ($root); my @pendingSections; while (<DATA>) { chomp; if (/<h(\d+)>(.*)/i) { # deal with a header line # First pop any pending sections that need to be closed pop @pendingSections while @pendingSections > $1; while (@pendingSections < $1) { # Add section elements out to current header level my $level = @pendingSections + 1; my $elt = new XML::Twig::Elt ("section$level"); if ($level == 1) { $elt->paste (last_child => $root); } else { $elt->paste (last_child => $pendingSections[-1]); } push @pendingSections, $elt; } my $headElt = new XML::Twig::Elt ("head", $2); $headElt->paste (last_child => $pendingSections[-1]); } else { # It's a paragraph if (@pendingSections) { $pendingSections[-1]->suffix ("$_\n"); } else { $root->suffix ("$_\n"); } } } $twig->print (); __DATA__ <h1>Heading level 1 <h2>Heading level 2 <h3>Heading level 3 <h2>Heading level 2 <h1>Heading level 1 paragraph here paragraph here [download] Prints: `<root> <section1> <head>Heading level 1</head> <section2> <head>Heading level 2</head> <section3> <head>Heading level 3</head> </section3> <head>Heading level 2</head> </section2> <head>Heading level 1</head>paragraph here paragraph here </section1> </root>` [download] which isn't quite what you showed (especially the root element), but does do the parsing/rendering magic it seems you may be after. DWIM is Perl's answer to Gödel	[reply] [d/l] [select]
Re: nested level section closing by shmem (Chancellor) on Mar 14, 2007 at 11:50 UTC
Your help will be very useful for me. Not enough information to help, really. See I know what I mean. Why don't you? What transformation rules do you follow to get the output from the input? Where is the code that does the transformation? What output is expected? Please post more information. --shmem _($_=" "x(1<<5)."?\n".q·/)Oo. G°\ / /\_¯/(q / ---------------------------- \__(m.====·.(_("always off the crowd"))."· ");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}	[reply]
Re: nested level section closing by ww (Archbishop) on Mar 14, 2007 at 12:10 UTC
AM -- As you can perhaps see from the answers above, you've handed us a puzzle; not a comprehensible question. What is your question? Where is your code? Please see How do I post a question effectively? for invaluable hints (and, hint: that should be "mandatory reading!"] for SoPW.	[reply]
Re: nested level section closing by Samy_rio (Vicar) on Mar 14, 2007 at 11:50 UTC
Hi Anonymous Monk, try like this using Regular Expression, use strict; use warnings; my $input = do{local $/; <DATA>}; $input =~ s/(<(h\d+>)[^\n]+)/$1<\/$2/gsi; $input =~ s/(<h(\d+)[^>]>)(.?)(?=(<h(\d+)[^>]>))/"$1".&section_clos +e($2,$3,$5)/egsi; $input =~ s/(<(h\d+>)){2,}/$1/gsi; ######Last level if ($input =~/<h./si) { if ($input =~/(<h\d+[^>]>)(.)(<h(\d+)[^>]>)(.)$/si) { $input =~s/(<h\d+[^>]>)(.)(<h(\d+)[^>]>)(.)$/"$1$2$3".&sec +tion_close($4,$5,1)/egsi; } else { $input =~s/(.)(<h(\d+)[^>]>)(.)$/"$1$2".&section_close($3,$ +4,1)/egsi; } } ############Heading replacement $input =~ s/(<h(\d+)>)((?:(?!<\/h\2>).)*)<\/h\2>/$1<head>$3<\/head>/gs +i; $input =~ s/(<\/?)h(\d+>)/$1section$2/gsi; print $input; sub section_close { my ($csect_no,$aft_txt,$asect_no)=@_; my $tag_close; if ($csect_no == $asect_no) { $tag_close="$aft_txt<\/h$csect_no>\n" } if ($csect_no < $asect_no) { my $j = $asect_no - $csect_no; my $i = $csect_no; my $temp = ""; while ($j > 1) { my $k = $i + 1; $temp = $temp."<h$k>\n"; $i++; $j--; } $tag_close = "<h$csect_no>".$aft_txt.$temp; } if ($csect_no > $asect_no) #head separation { my $temp = ""; my $i = $asect_no; for ($i = $asect_no; $i <= $csect_no; $i++) { $temp = "<\/h$i>\n".$temp; } $tag_close = $aft_txt.$temp; } return $tag_close; } __DATA__ <h1>Heading level 1 <h2>Heading level 2 <h3>Heading level 3 <h2>Heading level 2 <h1>Heading level 1 paragraph here paragraph here Output: ------- <section1><head>Heading level 1</head> <section2><head>Heading level 2</head> <section3><head>Heading level 3</head> </section3> </section2> <section2><head>Heading level 2</head> </section2> </section1> <section1><head>Heading level 1</head> paragraph here paragraph here </section1> [download] Regards, Velusamy R. eval"print uc\"\\c$_\""for split'','j)@,/6%@0%2,`e@3!-9v2)/@\|6%,53!-9@2~j';	[reply] [d/l] [select]
Re: nested level section closing by marto (Cardinal) on Mar 14, 2007 at 10:25 UTC
Hi, welcome to PerlMonks Firstly your input is not valid HTML, since each heading tag should have a closing tag: `<h1>Heading level 1</h1> <h2>Heading level 2</h2>` [download] And so on. Fixing this may be advantageous before starting to parse the data. I think you should take a look at using a combination of HTML::TokeParser (some people prefer HTML::TokeParser::Simple or HTML::TreeBuilder) and HTML::Template. Using HTML::TokeParser (or similar) to get the data structure (see Working with HTML from the tutorials section of this site for further info), and HTML::Template to format the HTML in the way you want to based on the data structure you have as a result from parsing your input (see Framework, Templating, and Content Management Systems from the tutorials section of this site). The modules are well documented. If you need help installing modules look at Modules: How to Create, Install, and Use from the tutorials section of this site. If you have any further problems, post any code and error message(s) you have. Update: fixed typo Hope this helps Update:It would seem I have 'jumped the gun' as they say, please disregard this advice. Martin	[reply] [d/l]

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